#41580 [NEW]: preg_replace returns NULL, not the unmodified string

From: steponas at idamas dot net Operating system: All PHP version: 5.2.3 PHP Bug Type: PCRE related Bug description: preg_replace returns NULL, not the unmodified string Description: ------------ Hello, the problem is, on this specific string (which I managed to write by accident) preg_replace returns NULL, not the unmodified string (because the regexp isn't matched). The funny thing is, if I remove some chars from the end of the string, or if I remove all "[quote]" ocurences from the search string, or if I provide a closing tag for the quote ([/quote]) - it works ok (returns the original string). And this bug (as I see it) is found only in PHP 5.2.*. My current sysinfo: Windows XP sp2 PHP 5.2.3 as Apache2.2 cli (from binary .zip) PCRE Library Version 7.0 18-Dec-2006 PHP versions I tested it on: 5.2.3 - bad 5.2.1 - bad 5.2.0 - bad 5.1.6 - ok, returns the string 4.3.10 - ok 4.3.2 - ok It works the same on linux and windows. Reproduce code: --------------- <?php header("Content-type: text/html; charset=utf-8"); ?> <pre> <?php //base64_encoded, because it's UTF-8, Lithuanian $string = base64_decode("VcW+ZHJhdXN0YSBmb3J1bXVvc2UgcmHFoXl0aSBjaXRhdMWzIHBha2xvZGVz". "IC0gdC55LiwgamVpZ3UgcmHFoXlzaXRlIDMtaXItZGF1Z2lhdSBuZQ0KdcW+ZGFyeXRhcyBjaW". "F0YXRhcyAoW3F1b3RlXS4uLltxdW90ZV0uLi5bcXVvdGVdLi4uKSwgdGFpIGp1bXMgYnVzIGFw". "aWUgdGFpIHByYW5lxaF0YSBpciDFvmludQ0KdMSXIG5lYnVzIGnFoXNpxbNzdGEgLSBz"); echo "The string is:\n".$string."\n\n"; echo "PHP: ".phpversion()."\n"; $regexp = "/\[quote\]((\s|.)*)\[\/quote\]/i"; echo (preg_match($regexp, $string) == true ? "Match found\n" : "Match not found\n"). "var_dump( preg_replace(...) ): "; var_dump( preg_replace($regexp, "<span style='background_color: yellow;'>\$1</span>", $string) ); ?> </pre> Expected result: ---------------- var_dump( preg_replace(...) ): <The original string> Actual result: -------------- var_dump( preg_replace(...) ): NULL -- Edit bug report at http://bugs.php.net/?id=41580&edit=1 -- Try a CVS snapshot (PHP 4.4): http://bugs.php.net/fix.php?id=41580&r=trysnapshot44 Try a CVS snapshot (PHP 5.2): http://bugs.php.net/fix.php?id=41580&r=trysnapshot52 Try a CVS snapshot (PHP 6.0): http://bugs.php.net/fix.php?id=41580&r=trysnapshot60 Fixed in CVS: http://bugs.php.net/fix.php?id=41580&r=fixedcvs Fixed in release: http://bugs.php.net/fix.php?id=41580&r=alreadyfixed Need backtrace: http://bugs.php.net/fix.php?id=41580&r=needtrace Need Reproduce Script: http://bugs.php.net/fix.php?id=41580&r=needscript Try newer version: http://bugs.php.net/fix.php?id=41580&r=oldversion Not developer issue: http://bugs.php.net/fix.php?id=41580&r=support Expected behavior: http://bugs.php.net/fix.php?id=41580&r=notwrong Not enough info: http://bugs.php.net/fix.php?id=41580&r=notenoughinfo Submitted twice: http://bugs.php.net/fix.php?id=41580&r=submittedtwice register_globals: http://bugs.php.net/fix.php?id=41580&r=globals PHP 3 support discontinued: http://bugs.php.net/fix.php?id=41580&r=php3 Daylight Savings: http://bugs.php.net/fix.php?id=41580&r=dst IIS Stability: http://bugs.php.net/fix.php?id=41580&r=isapi Install GNU Sed: http://bugs.php.net/fix.php?id=41580&r=gnused Floating point limitations: http://bugs.php.net/fix.php?id=41580&r=float No Zend Extensions: http://bugs.php.net/fix.php?id=41580&r=nozend MySQL Configuration Error: http://bugs.php.net/fix.php?id=41580&r=mysqlcfg